The present invention relates to a method for operating a drive control device, wherein the drive control device comprises at least one bus port and a communication interface for connecting to a bus and for sending and receiving data over the bus.
The following discussion of related art is provided to assist the reader in understanding the advantages of the invention, and is not to be construed as an admission that this related art is prior art to this invention.
Drive control devices of said type, e.g. for connecting electric motors, are known per se. The performance and functionality of such drive control devices have constantly increased over the last several years, with the result that a multiplicity of additional functions in addition to, for example, frequency conversion, speed control or rotational speed regulation are provided. An example of an additional functionality of this type is the possibility of connecting such drive control devices to a bus, e.g. a fieldbus or the like, and accordingly to integrate the drive control device, together with further communication subscribers, into an automation system in which each communication subscriber, i.e. including the drive control device, can be reached. Given such reachability of the drive control device via a bus it is possible to configure or parameterize the drive control device centrally. Furthermore, it is also possible to query and/or continuously monitor the status of the drive control device from a central point.
In order to improve the ability to control and use such measures by a user accessing the respective drive control device, not directly, but from a central point, e.g. a master control station or the like, consideration was given in the prior art to providing the functionality of what are called web servers on drive control devices of the above-described type. Such a web server manages at least one predefined or predefinable web page in which a visualization of e.g. system or operating parameters of the drive control device and/or currently valid measured values in relation to a mode of operation of the drive control device can be contained in summary form. Currently valid measured values may include e.g. a current rotational speed of a connected motor. The result for the user when the corresponding web page is called is a clearly organized presentation of the data incorporated in the web page. The effect of the functionality as a web server is that data and explanatory texts are or can be combined in a simple manner in an attractively formatted way and that such information is presented at a requesting station, e.g. the master control station in the example chosen here, as the unit accessing the web server of the drive control device.
Even if this additional set of functions of drive control devices is extremely useful and helpful, an obstacle to providing such functionality in the drive control device is, however, that on the one hand such functionality takes up storage space in a memory of the drive control device and on the other hand occupies further resources during the operation of the drive control device, namely it not only costs computing time, but also reduces the volume of data which can be transferred over the bus and to the drive control device in one time unit if an access to the web server incorporated in the drive control device also takes place in the time unit.
It would therefore be desirable and advantageous to obviate or at least reduce the effects of prior art shortcomings and to provide an improved method for operating a drive control device and to also provide a drive control device which can be used in such a method, wherein the aforementioned disadvantages are avoided.